After a few years of explosive growth, the self-publishing gold rush has finally slowed down.

“While self-publishing is alive and well and still showing very healthy growth rates, gone are the days of 60% growth year over year. As the charts in this report show, self-publishing has matured and slowed down to a steadier, less frantic pace.”

When reading the full report and the detailed statistics for both books and e-books, there are a few telling facts. One is by omission, in that there is no data for Amazon KDP. This makes it difficult to gauge the full picture. As Amazon use their own ASIN number to identify their e-books, and Bowker uses ISBN numbers to gather their statistics, this leaves a gaping hole in the report.

The only possible way to gather information on the number of Kindle e-books published is by having an Amazon Associates account to access this information. As I write this, there are 3,533,595 titles available on the Kindle Store.

I wrote an article on this method on 22nd August, and the total then stood at 3,393,009. In less than two months this is an increase of 140,000 titles. When reading the statistics cited in Bowker’s report, it is very easy to understand that other e-book publishers pale by comparison to Amazon’s market dominance.

The other interesting statistical evidence is the continued decline in vanity publishing, and in particular, Author Solutions and its number of subsidiaries and offshoots. While the battle has often been labelled as self-publishing against traditional publishing, it would seem that vanity publishing got caught in the middle, and it being squeezed from both sides.

Lastly, after exponential growth in its first four years of operation, Smashwords slowed a little in 2013 according to the data. As the report states, this shows that the e-book market is showing signs of reaching a level of maturity. But the data also confirms that Smashwords is, after Amazon KDP, the second biggest e-book publisher, and by a long distance.